Verifying Interface Properties

Purpose

Verify that the interface properties are correct.

Action

From the CLI, enter the show interfaces detail command.

Sample Output

Physical interface: ge-1/0/0, Enabled, Physical link is Up
  Interface index: 134, SNMP ifIndex: 27, Generation: 17
  Link-level type: Ethernet, MTU: 1514, Speed: 100mbps, Loopback: Disabled,
  Source filtering: Disabled, Flow control: Enabled
  Device flags   : Present Running
  Interface flags: SNMP-Traps 16384
  Link flags     : None
  CoS queues     : 4 supported
  Hold-times     : Up 0 ms, Down 0 ms
  Current address: 00:90:69:87:44:9d, Hardware address: 00:90:69:87:44:9d
  Last flapped   : 2004-08-25 15:42:30 PDT (4w5d 22:49 ago)
  Statistics last cleared: Never
  Traffic statistics:
   Input  bytes  :                    0                    0 bps
   Output bytes  :                    0                    0 bps
   Input  packets:                    0                    0 pps
   Output packets:                    0                    0 pps
  Queue counters:       Queued packets  Transmitted packets      Dropped packets
    0 best-effort                    0                    0                    0
    1 expedited-fo                   0                    0                    0
    2 assured-forw                   0                    0                    0
    3 network-cont                   0                    0                    0
  Active alarms  : None
  Active defects : None

Meaning

The output shows a summary of interface information. Verify the following information:

• The physical interface is Enabled. If the interface is shown as Disabled, do one of the following:
  • In the CLI configuration editor, delete the disable statement at the [edit interfaces interface-name] level of the configuration hierarchy.
  • In the J-Web configuration editor, clear the Disable check box on the Interfaces>interface-name page.
• The physical link is Up. A link state of Down indicates a problem with the interface module, interface port, or physical connection (link-layer errors).
• The Last Flapped time is an expected value. The Last Flapped time indicates the last time the physical interface became unavailable and then available again. Unexpected flapping indicates likely link-layer errors.
• The traffic statistics reflect expected input and output rates. Verify that the number of inbound and outbound bytes and packets matches expected throughput for the physical interface. To clear the statistics and see only new changes, use the clear interfaces statistics interface-name command.

Related Topics

For a complete description of show interfaces detail output, see the JUNOS Interfaces Command Reference.